The invention relates to the field of tissue engineering and medical transplantation technology. More particularly, the invention relates to a method for preparing an artificial biological tissue construct and to the use of cells obtained specifically, more particularly autologous cells, for said preparation method, further colonization methods or cell transplantation.
In the field of tissue engineering, work has been carried out for over 30 years to replace, as equivalently as possible, endogenous materials, such as organs, vessels or else tissue patches, with artificial constructs prepared in the laboratory and composed of biological and possibly endogenous materials. These constructs are envisaged as medical transplants. In the broadest sense, these also include cell transplants, for example for the reconstruction of ischemic tissue.
There is a very high demand for tissue engineering products. In this connection, biocompatibility is paramount. As far as possible, the artificial construct ought to be accepted in the body such that it is not recognized as being foreign and no pathological reactions are triggered. The construct must also be immediately functional.
In the field of activity, there are still particular problems in the exact reproduction of biological tissue with regard to the spatial arrangement of the cells contained therein, their connection to one another, including correct cell communication, cell function and tissue blood supply.
A subproblem consists in introducing cultured cells into a construct when there is still no way of supplying blood to the cells (vascularization).
WO 2008/063753 A1 is concerned with the administration of endothelial progenitor cells (EPC) into injured tissue in order to induce neovascularization there.
Robert E. Verloop et al. describe in “Eur. Cytokine Netw.”, vol. 20, no. 4, 2009, 207-209, how EPCs influence angiogenesis in tissue preparations. For this purpose, an investigation is carried out of, inter alia, the chemokinesis and chemotaxis of the EPC on substrates coated with endothelial cells.
A further subproblem consists in ensuring cell adhesion on artificial materials, which are used in some cases for the mechanical reinforcement of the constructs. Even if these are biodegradable materials which are reshaped in the body to form endogenous structures (remodeling), there are problems at the start with cell adhesion and the formation of confluent surface films.
It is an object of the invention to achieve advances in the colonization of tissue constructs with living cells or the seeding of cells into living tissue with regard to the true-to-nature and biocompatible assembly of the outcome of the colonization and to specify an improved method for the preparation of tissue constructs.
This object is achieved by means of the features of the method according to claim 1 and of the use according to claim 9. The heart of the invention can be considered to be that of it being possible for a cell culture obtained in a particular way and containing cells obtained specifically, viz. especially endothelial progenitor cells and possibly further cells, to be used very advantageously for the desired purposes, i.e. cell transplantation and the preparation of bioartificial tissue constructs. In a further aspect of the invention, an especially advantageous preparation method or colonization method for a tissue construct is specified.